This invention relates to novel processes employing t-alkyl peroxy-2-alkyl-2-arylacetates (A) as free radical initiators for improved vinyl monomer polymerization processes and as curing catalysts for improved unsaturated polyester resin composition curing processes.
There is a need in the polymer industry for increasing the production capacity of polymer production facilities without having to simultaneously build additional expensive production facilities especially in times of high inflation and high interest rates. It has been found that the t-alkyl peroxy-2-alkyl-2-arylacetates of this invention which are derived from substituted acetic acids that contain no more than one alpha-aryl substituent and at least one alpha-alkyl substituent, are significantly more efficient initiators for polymerizing vinyl chloride monomer to PVC than are commercially available t-butyl peroxyneodecanoate (three alpha-alkyl substituents) or the art compound, t-butyl peroxydiphenylacetate (two alpha-aryl substituents). These invention peroxyesters have, also, been found to be much more effective curing catalysts for unsaturated polyester resin compositions than were commerical peroxyesters such as t-butyl peroxypivalate.